A roadway light fixture (or luminaire) may include an incandescent lamp, a high intensity discharge (HID) lamp, or one or more banks of light-emitting diodes (LEDs). The luminaire may include a reflector and a lens that cooperatively function to illuminate specific parts of the roadway. Traditionally, the reflector may have included several disjointed sections that were placed at specific locations within the body of the luminaire in order to reflect light from the light source in a particular direction.
In luminaires that make use of incandescent or HID lamps, it may be relatively difficult to control the directionality of the lighting since incandescent and HID lamps are omnidirectional light sources. For example, in spite of having a reflector and a lens, a luminaire that has an incandescent or an HID lamp may produce light vectors that exit the luminaire and illuminate regions adjacent to the roadway that need not be illuminated. This may result in light trespass issues, but more fundamentally, in a waste of energy. Thus, from a technical standpoint, LEDs are a viable alternative to incandescent and HID lamps; they provide relatively more directional light output and high energy efficiency.
Recent advances in LED manufacturing technologies and increases in demand for energy-efficient luminaires has contributed in increasing the demand for LED-equipped light fixtures. However, it still remains cost-prohibitive to mass-produce luminaires that make use of LEDs, simply because the assembly of such luminaires may require many more parts when compared to the assembly of their incandescent and HID-based counterparts. Accordingly, there is a need to provide LED-based luminaires that use very few components without compromising optical efficiency. Such LED-based luminaires would be relatively less costly to produce and service and thus would provide an economical alternative to incandescent and HID-based light fixtures.